Electric signaling system.



S. M. YOUNG & F. TOWNSEND.

ELECTRIC SIGNALING SYSTEM.

APPLICATION FILED NOV. 2]. I903.

Patented Sept. 21, 1915.

2 SHEETS-SHEET I.

% INVENTORS MM AZTORNEY I WW.

S. M. YOUNG & F. TOWNSEND.

ELECTRIC SIGNALING SYSTEM. APPLICATION FILED Nov.21, 1903.

Patented Sept. 21, 1915.

2 SHEETS-SHEET 2.

m mvrlmw COLUMBIA PLLNOCIRAPH 60-.WA5HINGTON, n. I;

UNITED STATES PATENT OFFICE.

SAMUEL ans YOUNG [AND irrrznuen TOWNSEND, or new YonK, n. Y., ASSIGNORST0 SAID YOUNG.

ELECTRIG Sl-GHALING Specification of Letters Patent.

Patented Sept. 21, 1915.

Applicatien filed November 21, 1,993. Serial Ho. 182,079.

To aZZ whom it may cazwflra:

Be it known that WQ, SAMI IEL 'MA BH YOUNG and FITZl-IUGH Townsnnn,citizens ,of the United ;States, residing at New Ycrk city, county andState of New York, have invented certain new and useful Improve.- mentsin Electric Signaling Systems, of which the following isa specification.

The invention relates to automatic block signaling system for electricrailways.

In prior applications, filed the name of Samuel Marsh Young, SerialNumbers le s-is, 154,275, 160,086, there is described a system ofautomatic Jolocl; signaling for electric railways embodying two sourcesof current differing in character, .ontgoing feeder conductors leadingtherefrom, a trackway formed of two rails, divided into a series ofsections, means for creating a .difference of potential between therails .of each section, a signaling device each-sec.-

tion, normally energized by such difference of potential and heldthereby in the clear position and deenergized to move to the dangerposition, and be maingtamed in'such position when a .car moves into asection, and means introduced between separated ends .of one rail of.each section for electrically separating adjacent sections, so far asrelates to the current employed {to actuate the signaling devices saidsections, but which permit both rails of all of'the sections to serve asa common return or both our rents.

Our present invention, while it may :be said to embody the generalprinciple of operation set forth in the above mentioned applications,differs therefrom in the follow ing particulars:

First: Instead of using two sources of electrical energy generatingcurrents diflering in character, we may use ;a single source ofelectrical energy, or two sources of electrical energy of the samecharacter, but differing in phase or frequency.

Second: Instead of creating the required difference of potential betweenthe .opposite rails of each section by means of -a single transformer,having its pr mary connected across the source ofenergy and itssecondaryacross the rails, we create the required potential in a block-by meansof atwo transformers, which have their primaries connected in parallelacross the source v of ,energy and their secondaries wound inpopposition and connected in parallel across the rails. A pair oftransformers are located at each end of a Section, with theirsecondaries connected in series across the divided ends of .0116 rail ofadjacent sections. IVe may also make. use of another transformer in each'blOQk, having its primary connected across the source of energy and itssecondary across the rails.

Third: Instead of using a relay device, in each section, which Serves toopen and close a local circuit, and thus control the movement of thesignaling device in one direction, we employ a motor device, having onemember connected acrossthe source of energy. d the other member acrossthe rails of the section.

The advantages of the present (arrangement of parts over those describedin the applications above mentioned are: (a) The number of sources ofenergy or currents used may be decreased. (6) The electricalindividuality of the sectiops'so far as relates to the current used tooperate the signaling devices, is more distinct. (0) The amperage of thecurrent transmitted to the rails for operating the signals in eachsection may be largely increased, without correspondingly increasing the,difierence of potential between the rails. (cl) The employment of arelay and local circuit is done away with.

The accompanying diagrams will serve to illustrate our invention.

Figure l is ,a diagram showing the general arrangementof the system,where one source of alternating current is employed. Fig. 2 is acorresponding diagram, showing the same eneral arrangement, with theaddition 0'; resistance in the circuits of the cur rent transformingdevices. Fig. 3 is a ,diagram showing the general arrangement of thesystem, where two sources of alternating current energy are employed.Fig. 4 is a similar diagram, showing the general arrangement of thesystem, where one source of direct current and one source of alternatingcurrent are-employed. Fig. 5 is an enlarged view of a portion of therail-bond used in the construction shown in Fig. 4:.

Referring to the diagrams: In Figs. 1 and 3, the trackway is shown asdivided into four sections, A, B, C, D, in Figs. 2 and 4, into threesections, A, B, C. Manifestly, the number ,of sections will .dependuponthe leng f ro d, an t e l ng ,ofea sec tion @may be such as.desired.

10 indicates an alternating generator, connected in Figs. 1, 2, 3,across the feeder con- V ductor 11, and the two track-rails 12, 13. In

Figs. 1 and 2 the generator 10 is assumed to be of suflicient capacityto operate the car motors and the signaling devices; and in Fig. 3 tooperate the car motors. In Figs. 3 and 1, a second alternatinggenerator, 14:, is shown connected across the feeder conductor 15 andthe track-rails 12, 13. erator 1A is assumed to be sufiicient capacityto operate the signaling devices.

In the construction shown in Fig. 3, the generators 10, 1 1, while bothalternating generators, may have their currents differentiated either asto phase or frequency; as for instance, one generator may deliver acurrent of 25 cycles and the other 100 or more cycles. It will beunderstood by electricians', without further description, that a phaseor the phases of one current may be used to operate the car motors and aphase or the phases of the other current to actuate the signalingdevices; or, a current of one frequency to operate the car motors, andthat of the other frequency to operate the signaling devices, and thatthere will be no intermingling of such currents. Or, in other words,that each current will perform its office irrespective of the other, andirrespective of the fact that both are impressed upon the two rails ofthe system as a common return.

16, Fig. 41, indicatesa direct current generator, connected across thefeeder conductor l1 and the two rails 12, 13.

17 indicates a car carrying a motor 18, one terminal of which isconnected to the axle 19, on the ends of which are the wheels 20.

In the construction shown in Figs. 1 and 2, the alternating current fromthe generator 1O actuates the car motors, creates the difference ofpotential between the rails, and actuates the signaling devices. In theconstruction shown in Fig. 3, the generator 10 actuates the car motors,and the generator 14. creates the difference of potential between therails, and actuates the signaling devices. In the construction shown inFig. 4 the direct current generator actuates the car motors, and thealternating current generator 1 1 creates the difference of potentialbetween the rails and actuates the signaling devices.

The electrical individuality of the sections A, B, C, D, of the trackwayis obtained in the manner which we will now proceed to describe.

In the former applications referred to, a reactance bond was interposedbetween the ends of the rail 13 of adjacent sections, and further, areactance cross-bond was used. The effect of using the reactance. bondbetween the ends of the rail 13 was two-fold: First, to increase theelectrical resistance The gen-,

from one section to the next; as for instance,

from A to B, while permitting thepassage of the power current used tooperate the car motors. This device, in practice, proved to besatisfactory, but is open to the objection, that the total resistance ofthe rail 13 to the power current is greater than that of the rail '12.Or, in other Words, the reactance bonds interposed an impedance in thereturn path of the currents to the generator or generators. y

In the present case there is substituted for each reactance bond twotransformers 21, 22, the primaries of which 23, 24, are connected inparallel across the feeder conductor 11 and one rail 12, Figs. 1 and 2;or, asshown in Figs. 3 and 4c, in parallel across the feeder conductor15 and the rail 12. The secondaries of these transformers, 25, 26, arewound in opposite directions on the transformers 21, 22, and connectedto the ends of the adjacent sections of the rail 13. In all of thefigures, each secondary makes a minimum of one turn around the core ofthe transformer. The object of using one turn is to avoid the impedanceeflect due to a number of turns especially where the power current is analternating current. In cases where the power current is a directcurrent, the number of turns may be increased, with a correspondingdecrease in the amount of iron in the core of the transformer. Thearrangement shown also greatly diminishes any magnetization of the coresof the transformers 21, 22 by the power current used to operate the carmotors. A conductor 27 connects a central point between the secondaries25, 26 with the rail 12. It will be observed that the secondaries are inparallel across the rails 12, 13, and in series between the ends ofadjacent rails 13. A third transformer 28, is also employed in eachsection, having its primary 29 connected across, in Figs. 1 and 2, thefeeder conductor 11 and the rail 12, or in Figs. 3 and 41, across thefeeder conductor 15 and the rail 12, and its secondarv 30 across therails 12, 13. 1 V

It will be seen from the above that there are three transformers in eachsection, in section B, for instance, the transformer 22 at the 'left,transformer 21 at the right, and transformer 28 in the section, and thatthe difference of potential between the rails 12. 13 is derived from thesecondaries of these transformers; and further, that the transformers21,22, whether located adjacent at the end of a section, or separated bythe length of a section, are wound to oppose each other.

It will further be observed that if the conducting capacity of thesecondaries of the transformers 21, 22 in series, is made equal per unitof length to that of the rail 13, the rail in fact will act as onecontinuous rail and present approximately the same resistance to thepassage of the power current used to operate the motors, as is presentedby the rail 12. Or, in other words, the efi'ect of the construction isto increase the con ducting capacity of the rails 12, 13, over that of asystem where reactance bonds are used instead of transformers.

If desired, and'in order to prevent absolute short circuiting of thesecondaries ofthe transformers 21, 22, 28, resistance 31 may beintroduced in such secondaries, as shown in Fig. 2, and a similarresistance 32, may, if desired, be introduced in the primaries.

Instead of using such resistance in the secondaries, we may use thearrangement shown in Figs. 4 and 5. In this arrangement, a sleeve ofiron 33 is placed over the secondaries 25, 26, 30. Magnetic whirls areset up in this sleeve concentrically to the secondary winding, therebyproducing a counter-electro-motive force which causes a drop in thevoltage and prevents a dead short circuit. The sleeve, therefore, actsas an impedance; the effect being the same as putting a resistance orreactance in the primary or secondary windings.

It now remains to describe the signaling device employed in eachsection. This may be constructed in a variety of ways. Preferably weprefer to use an electro-motor 34.

The field-magnets 35 of this motor are connected across the rails 12,13, and its armature 36 across, in Figs. 1 and 2, the feeder conductor11 and the rail 12, and in Figs. 3 and 4, the feeder conductor 15 andthe rail 12. Connected to the armature of this motor is a crank 37,which is connected through a link 38 to a counter-weight semaphore arm39.

The operation of the system is as follows: Normally, that is, when nocar is on a section, a difference of alternating signal potential existsbetween the rails 1213 and the current due to this difierence ofpotential will divide between the two paths open to it, inversely astheir resistance and reactance, these two paths being (a) the paththrough the field magnets of the motor 34, and (b) the path around thefield magnets formed by the rails 1213 and the crossbond 27. It will ofcourse be understood by electricians that the resistance and reactanceof the path around the field magnets (i. e. the (b) path) will be suchthat sufficient current will be sent through the field magnets 6., the(a) path) to impart to such field magnets what is known as pick-upvalue, and as the armature 36 of the motor is excited from across thesource of signaling energy, a turning movement of the armature willresult, which will push the semaphore armto the danger position shown insections B, D, of Figs. 1 and 3 and C- in Figs. 2 and 4. -When a carmoves into a block, the secondary 30 of the transformer 28 is shortcircuited by means of the wheels 20 and axle 19, thereby destroying thedifference of potential between the rails, and in effect shortcircuiting the field-magnets 35 of the motor 34. At this time, thecounter-weight on the end of the semaphore arm acts and brings the armto the danger position shown in section C of all four figures. The caras it moves in the block varies the resistance of the secondaries of thetransformers 21, 22, at opposite ends of the block, but not sufficientlyso to materially efiect the opposing action of the transformers 21, 22,disposed at opposite ends of each section.

In this specification we have used the expression differing in characteras referring to the currents transmitted from the generators 10, 14, 14,16, that is, two currents differing in phase, two currents differing infrequency, two currents one alternating and the other direct, asdifferentiated from the expression differing in strength, as applied totwo currents.

We wish it understood that we do not limit ourselves to the specialmeans described for effecting the electrical independence of thesections, as manifestly means other than transformers may be employedwhere the reactance, retarding or opposing effect of the bond is createdby a current of different frequency passing througha conductor, used inconnection with or without an iron core.

Having thus described our invention, we claim In a signaling system forelectric railways, a plurality of track circuits each of which includesan inductive devicecomprising a core and a winding which is connectedwith one line of rails of the track circuit, an electrical connectionbetween adjacent inductive devices and the opposite line of rails, and asecond winding on each inductive device traversed by an alternatingsignaling current of higher potential than an alternating signalingcurrent traversing the first winding of the inductive device.

In testimony whereof we afiiX our signatures, in the presence of twowitnesses.

SAMUEL MARSH YOUNG. FITZHUGI-I TOl/VNSEND.

Witnesses:

J. E. PEARSON, FRANK OCoNNon.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

